How to add a torus to another shape
Select Non-Manifold Ctrl-Shift-Alt-M and delete vertices X.


Add two loop cuts Ctrl-R to ear-ring 
Add an additional edge F (selected in the image) 
Subdivide the new added edge W subdivide


This should look like:


Remove some loop cuts from half torus Alt-RMB , X loop-cut until the number of edges matches the other part.

Select two open ends and search for Bridge/Loft Space